"Ice" is the eighth episode of the first season of the American science fiction television series The X-Files, which premiered on the Fox network on November 5, 1993. It was directed by David Nutter and written by Glen Morgan and James Wong. The debut broadcast of "Ice" was watched by 10 million viewers in 6.2 million households and received largely positive reviews from critics, who praised its tense atmosphere.

The episode was inspired by an article in Science News about an excavation in Greenland, and series creator Chris Carter also cited John W. Campbell's 1938 novella Who Goes There? as an influence. Although the producers hoped that "Ice" would save money by being shot in a single location, it ended up exceeding its production budget.

Murphy finds an ice core sample believed to originate from a meteor crater, and theorizes that the sample might be 250,000 years old. Although Bear insists on leaving, the others are concerned about infecting the outside world. When he is asked to provide a stool sample, he attacks Mulder and tries to flee. Something moves under Bear's skin, and he dies when Hodge removes a small worm from the back of his neck. Now without a pilot, the group is informed that evacuation is impossible because of the weather.

The worm removed from Bear is kept in a jar, and another is recovered from one of the scientists' bodies. Mulder (believing that the worms are extraterrestrial) wants them kept alive, but Scully feels that they should be destroyed to prevent infection. The group check each other for black nodules and find none, although Mulder reminds Scully that the nodules disappeared from the dog over time. When Mulder finds Murphy in the freezer with his throat cut, the others (including Scully) believe that he has become infected and killed Murphy. Mulder is then locked in a storeroom.

Scully discovers that two worms put together will kill each other. When the investigators place one of the worms into the infected dog, it recovers. Against Scully's objections, Hodge and Da Silva try to place the other worm into Mulder and Hodge realizes that Da Silva is the true infected person. He and Mulder restrain the hysterical Da Silva and place the last worm inside her. When they are rescued, Da Silva and the dog are quarantined and the others are released. Although Mulder wants to return to the site, he is told that it has been destroyed by the government.[1][2]

Glen Morgan began writing the episode after he read a Science News article about men in Greenland who found a 250,000-year-old item encased in ice.[3][4] The setting—an icy, remote research base overcome by an extraterrestrial creature—is similar to that of John W. Campbell's 1938 novella Who Goes There? and its two feature-film incarnations: The Thing from Another World (1951), directed by Christian Nyby and produced by Howard Hawks, and The Thing (1982), directed by John Carpenter.[3][5] Chris Carter has cited them as the main inspirations for the episode.[4] As in the novella and films, the characters cannot trust each other because they are uncertain if they are who they seem to be.[3] Carter particularly enjoyed this aspect, because it pitted Mulder and Scully against each other and provided "a new look on their characters early on in the series".[6]

The similarity to Carpenter's version of The Thing was due in part to new production designer Graeme Murray,[11] who worked on Carpenter's film and created the complex in which the episode took place.[12] Although "Ice" was intended as a bottle episode which would save money by being shot in a single location,[4] it went over budget. According to Carter, The X-Files typically worked from a small budget and "every dollar we spend ends up on the screen".[12] As a bottle episode, "Ice" used a small cast and its interiors were filmed on a set constructed at an old Molson brewery site. The episode's few exterior shots were filmed at Delta Air Park in Vancouver, whose hangars and flat terrain simulated an Arctic location.[11] Carter said that he would have preferred to set the episode at the North Pole, but he believed that this was unfeasible at the time.[13]

For the worm effect, one member of the special effects department suggested putting a "baby snake" in a latex suit. After explaining that that couldn't be done, animal trainer Debbie Coe suggested using a "super mealworm" to achieve the desired effect.[14] The effect of the worms crawling in the host bodies was achieved with wires under fake skins, including a skin with hair for the dog.[6][14] Digital effects were used for scenes involving the worms swimming in jars and entering the dog's ear.[6] Although extra footage of the worm scenes was shot so they would last as long as intended if Fox's standards-and-practices officials asked for cuts, no edits were requested.[15] "Ice" was the first significant role in the series for makeup effects artist Toby Lindala, who become its chief makeup artist.[15] The dog used in the episode was a parent of Duchovny's dog, Blue.[16]Ken Kirzinger, who played one of the scientists killed in the episode's cold open, was the series' stunt coordinator.[17]

Although "Ice" is not directly connected to the series' overarching mythology, it has been described as "a portent to the alien conspiracy arc which would become more pronounced in the second season" with its themes of alien invasion and governmental conspiracy.[18] The episode is noted for exploring the relationship between its lead characters; Mulder and Scully's trust contrasts with the behavior of Hodge and DaSilva, who are united by a distrust of those around them. The pairs are "mirror images" in their approaches to partnership.[19]

"Ice" features two elements common to other works by Morgan and Wong: dual identities and the questioning of one's personality. In her essay "Last Night We Had an Omen", Leslie Jones noted this thematic leitmotif in several of their other X-Files scripts: "the meek animal-control inspector who is a mutant shape-shifter with a taste for human liver ["Squeeze"], the hapless residents of rural Pennsylvania driven mad by a combination of insecticides and electronic equipment ["Blood"], [and] the uptight PTA run by practicing Satanists ["Die Hand Die Verletzt"]".[20]

"Ice" originally aired on the Fox network on November 5, 1993, and was first broadcast in the United Kingdom on BBC Two on November 10, 1994.[23] The episode's initial American broadcast received a Nielsen rating of 6.6 with an 11 share; about 6.6 percent of all households with television and 11 percent of households watching TV viewed the episode,[24] a total of 6.2 million households and 10 million viewers.[24][25] "Ice" and "Conduit" were released on VHS in 1996,[26] and the episode was released on DVD as part of the complete first season.[23]

"Ice" was praised by critics. In The Complete X-Files, authors Matt Hurwitz and Chris Knowles called the episode a milestone for the fledgling series.[27] An Entertainment Weekly first-season retrospective graded "Ice" as A−, calling it "particularly taut and briskly paced".[5] On The A.V. Club, Keith Phipps praised the episode and gave it an A. According to Phipps, the cast "plays the paranoia beautifully" and the episode was "as fine an hour as this first season would produce".[28] "Ice" was included on an A.V. Club list of greatest bottle episodes, where it was described as "us[ing] its close quarters as an advantage".[29] A third A.V. Club article, listing ten "must-see" episodes of the series, called "Ice" "the first sign that this show had a shot at really being something special" and said that it "makes great use of claustrophobia and the uneasy but growing alliance between the heroes".[30]

Digital Spy's Ben Rawson-Jones described the episode's stand-off between Mulder and Scully as "an extremely tense moment of paranoia."[31] A New York Daily News review called the episode "potent and creepy", and said that its plot "was worthy of honorary passage into The Twilight Zone".[32] Matt Haigh called it "an extremely absorbing and thrilling episode" on the Den of Geek website, noting its debt to The Thing,[33] and Juliette Harrisson called "Ice" the "finest" stand-alone episode of the first season.[34] On the TV Squad blog, Anna Johns called it "a spectacular episode" with an "excellent" opening.[35] UGO Networks called the episode's worms among the series' best "Monsters-of-the-Week" and the cause of "much pointed-guns aggression".[36] In Tor.com, Meghan Deans compared the scene where Mulder and Scully inspect each other for infection to a similar scene in "Pilot"; in "Ice", both characters were equally vulnerable and (unlike the pilot scene) Scully was not portrayed as "an idiot".[37]Robert Shearman and Lars Pearson, in their book Wanting to Believe: A Critical Guide to The X-Files, Millennium & The Lone Gunmen, gave the episode five out of five stars. They called it "the most influential episode ever made", noting that the series reprised its formula several times during its run. Shearman felt that although their script was derivative, Morgan and Wong created "a pivotal story" by combining crucial themes from The Thing with a "well rounded" cast of characters.[38]

"Ice" was also considered one of the best episodes of the first season by the production crew. According to Carter, Morgan and Wong "just outdid themselves on this show, as did director David Nutter, who really works so hard for us. I think they wrote a great script and he did a great job directing it, and we had a great supporting cast".[39] Nutter said: "The real great thing about 'Ice' is that we were able to convey a strong sense of paranoia. It was also a great ensemble piece. We're dealing with the most basic emotions of each character, ranging from their anger to their ignorance and fear. It established the emotional ties these two characters have with each other, which is very important. Scaring the hell out of the audience was definitely the key to the episode".[39] Anderson said that "it was very intense. There was a lot of fear and paranoia going on. We had some great actors to work with".[39]